The overall goals of this project are to 1) determine the primary effect of morphine-like drugs on the cholinergic system in the mammalian brain and 2) compare the effects of barbiturates to determine if they act differently from the narcotics on this transmitter system. These studies will be pursued using brain slices in vitro to study the dynamics of ACh synthesis storage and release. The incorporation of radioactive precursors into ACh, the specific activities of the various ACh pools, and the specific activity of the ACh released will be determined under various conditions of stimulation and drug treatment. Synthesis of ACh will also be observed by determining the activity of choline acetylase.